A near-infrared telescope with an effective aperture diameter of 30 mm has been developed. The primary objective of the development is to observe northern bright stars in the J, H, and Ks bands and provide accurate photometric data on those stars. The second objective is to observe a belt-like region along the northern Galactic plane (|b| ≤ 5° and δ ≥ −30°) repeatedly, to monitor bright variable stars there. The telescope has been in use since 2016 December. The purpose of this paper is to describe the design and operational performances of the telescope, the photometric calibration methods, and our scientific goals. We show that the telescope has the ability to provide photometry with an uncertainty of less than $5\%$ for stars brighter than 7, 6.5, and 6 mag in the J, H, and Ks bands, respectively. The repeatability of the photometric measurements for the same star is better than $1\%$ for bright stars. Our observations will provide accurate photometry on bright stars that are lacking in the Two Micron Sky Survey and the Two Micron All-Sky Survey. Repeated observations at a good cadence will also reveal their nature in terms of variability in the near-infrared.
The radiance of sky brightness differs principally with wavelength passband. Atmospheric scattering of sunlight causes the radiation in the near-infrared band. The Antarctic is a singular area of the planet, marked by an unparalleled climate and geographical conditions, including the coldest temperatures and driest climate on Earth, which leads it to be the best candidate site for observing in infrared bands. At present, there are still no measurements of night-sky brightness at DOME A. We have developed the Near-Infrared Sky Brightness Monitor (NISBM) in the J, H, and Ks bands for measurements at DOME A. The instruments were installed at DOME A in 2019 and early results of NIR sky brightness from 2019 January–April have been obtained. The variation of sky background brightness with solar elevation and scanning angle is analysed. The zenith sky flux intensity for the early night at DOME A in the J band is in the 600–1100 μJy arcsec−2 range, that in the H band is between 1100 and 2600 μJy arcsec−2, and that in the Ks band is in the range ∼200–900 μJy arcsec−2. This result shows that the sky brightness in J and H bands is close to that of Ali in China and Mauna Kea in the USA. The sky brightness in the Ks band is much better than that in Ali, China and Mauna Kea, USA. This shows that, from our early results, DOME A is a good site for astronomical observation in the Ks band.
more » « less- Award ID(s):
- 1817099
- PAR ID:
- 10471364
- Publisher / Repository:
- Monthly Notices of the Royal Astronomical Society
- Date Published:
- Journal Name:
- Monthly Notices of the Royal Astronomical Society
- Volume:
- 521
- Issue:
- 4
- ISSN:
- 0035-8711
- Page Range / eLocation ID:
- 5624 to 5635
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1093/mnras/stad775
